Crash may occur when using “Static Component Mask Parameter” in “Material Layer”

When there are more than two “Static Component Mask Parameter” in “Material Layer” or “Material Layer Blend”, it will crash when you click Save and open the material instance with this “Material Layer” or “Material Layer Blend”.
The occurrence of this crash depends on the naming of “Static Component Mask Parameter”
Crash Reporter shows:
Assertion failed: (Index >= 0) & (Index <ArrayNum)
Array.h] [Line: 674] Array index out of bounds: 2 from an array of size 2

For example: When I named “Static Component Mask Parameter” “MTELSSIC”,no crash occurred:

But when I named MATELSSIC and Apply, crash occurred

This is so strange, why the crash is related to naming :sob: